A sedated rhinoceros lies unconscious as James Larkin (left) from the University of the Witwatersrand implants radioisotopes into its horns, along with other Rhisotope Project members in the Waterbury UNESCO biosphere in Mokopane, June 25, 2024.
| Photo Credit: Emmanuel Croset/AFP
South African scientists on Tuesday injected radioactive material into live rhinoceros horns to make them easier to detect at border posts in a pioneering project aimed at curbing poaching.
The country is home to a large majority of the world’s rhinoceroses and as such is a hotspot for poaching driven by demand from Asia, where horns are used in traditional medicine for their supposed therapeutic effect.
At the Limpopo rhinoceros orphanage in the Waterberg area, in the country’s northeast, a few of the thick-skinned herbivores grazed in the low savannah.
James Larkin, director of the University of the Witwatersrand’s radiation and health physics unit who spearheaded the initiative, said he had put “two tiny little radioactive chips in the horn” as he administered the radioisotopes on one of the large animals’ horns.
The radioactive material would “render the horn useless… essentially poisonous for human consumption,” added Nithaya Chetty, professor and dean of science at the same university.
The dusty rhinoceros, put to sleep and crouched on the ground, wouldn’t feel any pain, Mr. Larkin said. The radioactive material’s dose was so low it wouldn’t affect the animal’s health or the environment in any way, he added.
In February the environment ministry said that despite government efforts to tackle the illicit trade, 499 of the giant mammals were killed in 2023, mostly in state-run parks, an 11% increase over 2022 figures.
Twenty live rhinos in total are part of the pilot ‘Rhisotope’ project whereby they will be administered a dose “strong enough to set off detectors installed globally” at international border posts, originally “to prevent nuclear terrorism”, Mr. Larkin said.
Rhinoceros horns are highly sought after on black markets, where their price by weight rivals that of gold and cocaine.
According to Arrie Van Deventer, the orphanage’s founder, dehorning the rhinoceros and poisoning the horns have failed to deter poachers.
“Maybe this is the thing that will stop poaching”, the conservationist said. “This is the best idea I’ve ever heard.”
Wildebeest, warthogs, and giraffe roamed the vast conservation area as more than a dozen team members performed the delicate process on another rhinoceros.
Mr. Larkin drilled a small hole into the horn, hammered in the radioisotope, and finished off by spraying 11,000 microdots over the horn.
About 15,000 rhinoceroses live in the southern African nation, according to an estimate by the international foundation.
The last phase of the project will be the animal’s aftercare following “proper scientific protocol and ethical protocol”, project COO Jessica Babich said.
The team will then take follow-up blood samples to ensure the rhinoceroses are effectively protected. The material itself will last five years on the horn, resulting in a cost lower than dehorning every 18 months, Mr. Larkin said.
